(c) where a contributing institution is liable to be assessed to super profits tax under the Super Profits Tax Act, 1963 (14 of 1963 ), 1[ or to surtax under the Companies (Profits) Surtax Act, 1964 (7 of 1964 ),] in respect of its own income, profits or gains and receives any sum from the Trust under this Act in respect of its contribution to the initial capital, such sum as reduced by the amount of any income- tax and super- tax payable in respect thereof shall be excluded from the total income of the said institution in computing its chargeable profits for the purposes of super profits tax 1[ or surtax]. 2[ Explanation I.-- In this sub- section,-